Primary Chain Case - 250 0r 350?

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
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Martin.S
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Primary Chain Case - 250 0r 350?

Post by Martin.S »

So the models with the duplex primary chain had a wider outer chain case cover ie the CSRs and the 350s, So as I have bought a mix of parts how do I know which one I have?
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Rob Harknett
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Re: Primary Chain Case - 250 0r 350?

Post by Rob Harknett »

Do they have any numbers cast inside that may be the part number.
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Ozmadman
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Re: Primary Chain Case - 250 0r 350?

Post by Ozmadman »

Rob Harknett wrote:Do they have any numbers cast inside that may be the part number.
They do but cant remember what it is (350 one ends 061??? poss 42061 something like that)
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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Rob Harknett
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Re: Primary Chain Case - 250 0r 350?

Post by Rob Harknett »

Ozmadman wrote:
Rob Harknett wrote:Do they have any numbers cast inside that may be the part number.
They do but cant remember what it is (350 one ends 061??? poss 42061 something like that)
1960 parts lists state for outer chain case G2/G2CS. 042040. G5 044062. mod 14 /14CS. 042049. mod 8. 044063
I am sure AJS & Matchless for each c.c. will be the same, except the motif. If any numbers are damaged. or there were year changes, first 3 digits, if seen, may give a clue. 042 = 250 c.c. 044 = 350 c.c. ( That seems to be the norm, but some one may find different. You can always check the parts list for your own bike and see for yourself. )
Note: If you do not have a parts list or instruction book for your bike. These are the 2 parts that you need for the bike, before any other missing bits are sourced or work done on the bike. It will save you from asking many questions you can instantly discover yourself. This will leave those here willing to help others, deal more with the tech issues.
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Ozmadman
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Re: Primary Chain Case - 250 0r 350?

Post by Ozmadman »

Think all those differing numbers are because there is a badge on the chain case which will affect the part numbers, there are only two actual cases as far as i know? That number I mentioned (prefixed by a 0) is what I think the number (casting number?) is which is stamped on the inside
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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Rob Harknett
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Re: Primary Chain Case - 250 0r 350?

Post by Rob Harknett »

Part numbers do differ for AJS & Matchless because the part is stated as being with motif Paul. Perhaps that's why they often used a casting number instead of a part number. Perhaps the earlier numbering system was better, which started about the time Matchless broght AJS. You had numbers prefixed STD common to both marques, fitted various models and years. Also the numbers like 37-12- E11. 37= year of introduction, 12 smallest model it fitted E engine part. F frame, FF front fork etc.
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clanger9
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Re: Primary Chain Case - 250 0r 350?

Post by clanger9 »

CSRs don't have a motif, so that's another variation...
1989 Moto Morini Dart 350
1993 Ducati 750SS
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Rob Harknett
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Re: Primary Chain Case - 250 0r 350?

Post by Rob Harknett »

clanger9 wrote:CSRs don't have a motif, so that's another variation...
But in 1960 parts list G2 is the same as G2CS which says with motif. I only have 58 G2, 63 14 CSR & 66 G2CSR, cant see on the first 2 bikes, but my can see my 66 G2CSR which has no motif. Refer to the 62 /66 supplement as to which year and model there was and was not a motif. You will then know the years and modes the non motif outer front chain case is for. So this info alone will confirm date & model, of any non motif case. Also if its got a motif, it may be for a pre 62 model. So an additional clue as well as a pt. no.
http://archives.jampot.dk/book/Spares_l ... o_1966.pdf
Last edited by Rob Harknett on Fri Aug 24, 2018 10:59 am, edited 1 time in total.
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clanger9
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Re: Primary Chain Case - 250 0r 350?

Post by clanger9 »

Sorry, “later-model CSRs don't have a motif...”
1989 Moto Morini Dart 350
1993 Ducati 750SS
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Ozmadman
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Re: Primary Chain Case - 250 0r 350?

Post by Ozmadman »

Well, that's something else I have learned :beer:
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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